The use of wood in the construction of furniture for chairs, sofas and the like is well-known. Alternative materials such as metal or plastic have met with some success but, such success has been limited to specific areas. For example, U.S. Pat. No. 2,458,095 to O'Connor illustrates an example of the successful use of metal in seat construction for folding chairs. Metal has also successfully been used in seat frames for vehicle seats as disclosed in U.S. Pat. No. 4,623,114 to Sishino and U.S. Pat. No. 4,365,840 to Kehl et al.
However, metal frames have not been well received within the furniture industry for use in upholstered chairs, sofas or the like. Although metal frames are recognized as being sturdy, in the past, they have been much too heavy to be marketable or economically transported.
The inability of plastic to support the weight tolerances associated with conventional upholstered furniture and the shortcomings associated with past metal frames has resulted in the continued use of wood as the preferred material in frames for upholstered furniture. This is especially true of upholstered furniture which is to be used in residential homes and in industrial settings such as hospitals and office buildings.
Conventional wooden frames however tend to weaken and breakdown over a period of time. In addition, as wood becomes less available it correspondingly becomes more costly to produce wooden frames. Furthermore, wood only lends itself to permanent upholstery methods such as staples and does not allow the consumer to replace fabric without considerable effort, knowledge and tooling.
Low cost modular furniture which is lightweight yet sturdy, easy to produce, and which may be constructed in sub-assemblies which are easy to ship is desired by both consumer and retailer alike. In addition, consumers desire furniture which would allow them to replace the fabric or upholstery which was initially purchased as the upholstery is worn and/or goes out of style, without great cost or inconvenience.
U.S. Pat. No. 4,523,787 to Robinson generally discloses the ability to replace the upholstered panels of a sofa. Each of the replaceable back and side panels of the Robinson invention defines a hollow structure which slides over the respective back and arm of the frame. A front panel is removably attached to the metal frame by bolts. In this configuration, upholstered panels are used which are fit over the furniture frame rather than providing a metal frame which, when upholstered, cannot be distinguished from furniture made from a traditional wooden frame.
Therefore, the ability to manufacture a metal frame for upholstered furniture which has the same quality and appearance as a traditional wooden frame is desirable. In addition, it is desirable to produce a metal frame constructed of several easy to assemble sub-assemblies which is sturdy yet lightweight, while allowing quick and easy reupholstery.